Air cooled vacuum producing condenser



Sept. 15, 1964 w. KALS 3,148,516

AIR COOLED VACUUM PRODUCING CONDENSER Filed Jan. 21, 1963 3 Sheets-Sheet1 e9 68. 1 g)- ANOOQOOOOOOO w INVENTOR.

my. 2 Z

ATTOF/VEYB'.

Sept. 15, 1964 w, A 3,148,516

AIR COOLED VACUUM PRODUCING CONDENSER Filed Jan. 21, 1963 I 3Sheets-Sheet 2 w M INVENTOR.

AT T ORNE Y9.

Sept. 15, 1964 w, Ls 3,148,516

AIR COOLED VACUUM PRODUCING CONDENSER Filed Jan. 21, 1963 3 Sheets-SheetC5 INVENTOR s? z gj z:

grog/m6 United States Patent Oflice 3,143,516 A {IOOLED VACUUM PRODUCINGCONDENSER Waiter Kals, Hastings on Hudson, N.Y., assignor to NiagaraBlower Company, New York, N.Y., a corporation of New York Filed Jan. 21,1963, Ser. No. 252,748 12 Qlaims. (Cl. 62-3t35) This invention relatesto an air cooled vacuum producing condenser and more particularly tosuch a condenser of the evaporative type in which the cooling effect isobtained principally from the evaporation of water on the exterior ofthe tubes of the main condenser and intercondenser which are arranged inan air stream passing over these tubes.

This invention is an improvement on the condenser shown and described inmy Patent 2,570,247 dated Octoher 9, 1951.

In common with said patent, an object is to provide a large capacitysteam or vapor condenser cooled by the evaporation of water on theexternal surfaces of wetted tubes, such an evaporative condenser havingmany times the capacity of a dry coil of the same size and beingeconomical in the use of cooling water in that the water is evaporatedto use the latent heat of the water in providing the cooling effect.

Another object in common with said patent is to provide a vacuumproducing condenser in which the removal of air or non-condensible gasesfrom the vapor being handled is effected under conditions most favorableto the operation of a steam jet air ejector in ejecting the maximumamount of air from the system with the minimum consumption of steam,

Another object in common with said patent is to provide such a vacuumproducing condenser in which the cooling eifect is increased ordecreased in response to changes in the load on the condenser and inwhich the tubes are arranged and proportioned to provide a balancedsystem with a minimum of cooling surface.

A specific object of the present invention is to increase thedevaporization of the air-vapor mixture leaving the main andintercondenser tubes and before being admitted to the correspondingfirst and second stage steam ejectors, this being achieved by improvedremoval of entrained water in the headers through which the air-vapormixture passes and by cooling the devaporization or subcooling tubes toa lower temperature this being achieved by arranging these tubes to beserved by direct fresh air and recirculated water in contradistinctionto being served by air previously passed over the wetted main condensingtubes, as in said patent.

Another specific object is to provide such a vacuum producing condenserin which the main condenser, intercondenser and aftercondenser areserved by separate streams of air and in which all streams are producedby the same fan means and in a compact casing, the present condenserbeing characterized by down flow of the streams of air separatelythrough the main condenser, intercondenser and aftercondenser into thebottom of a central plenum chamber from which the air is dischargedupwardly.

Another specific object is to provide a reflux or drain lineforconduction condensate from a lower to a higher pressure header butotherwise isolating these headers from each other, this being achievedby providing a vertical leg in the reflux or drain line of such heightas to maintain a column of liquid therein of a height proportional tothe pressure differential between the two headers.

Another specific object is to provide concurrent flow of the air andwater sprays so that one does not impede the flow of the other.

Patented Sept. 15, 1964 Another specific object is to increase theefiiciency of the spray water system, this being achieved by segregatingthe lower temperature water serving the main condenser from the highertemperature water serving the intercondenser.

Other objects and advantages of the invention will be apparent from thefollowing description and drawings in which:

FIG. 1 is a simplified front elevational view of a vacuum producingcondenser embodying the present invention.

FIG. 2 is a simplified vertical transverse section therethrough lookingtoward the front thereof.

FIG. 3 is a simplified vertical longitudinal section taken through themain condenser section generally on lines 3-3, FIG. 1.

FIG. 4 is a simplified vertical longitudinal section taken through theintercondenser section generally on line 4-4, FIG. 1.

FIG. 5 is a simplified vertical longitudinal section through theaftercondenser section taken generally on line 55, FIG. 1.

The Shell The vacuum producing condenser of the present invention isshown as including a main sheet metal shell iii the bottom or base ofwhich includes a rectangular sump 11 extending centrally fore-and-aftthe full length of the sheil, and rectangular inclined bottom drainpanels 12, 13 serving to lead any falling water in the shell to thesump. The shell iii includes vertical side walls 14, 15 rising fromthose edges of the drain panels 12, 13 remote from the sump 11, andfront and rear walls 16, 1 8 connecting with the front and rear edges ofthe sump 11, drain panels 12, 13 and side walls 14, 15. The front andrear walls have central rectangular upward extensions i9, 26,respectively, forming the front and rear walls of a plenum'chamber 21,the side walls of which plenum chamher are formed by panels 22, 23 whichextend downwardly etween the front and rear walls 16, 18 toward the sump11.

The space bounded by the plenum chamber panel 22 and the front, rear andside walls 16, it; and T4, of the shell is open at its top and bottomand forms a main condenser chamber 25. The space bounded by the plenumchamber panel 23 and the front, rear and side panels 16, 18 and 15,contains a vertical partition 26 bridging this space between the frontand rear walls and forming with the plenum chamber panel 23 anintercondenser chamber 28, which. is open at its top and bottom. Thisvertical partition 26 forms with the side wall 15 an aftercondenserchamber 29 which is open at its top and bottom.

Air Flow Movement of outside air through the shell is effected by fans3% which are of the airplane propeller type and each driven by anelectric motor 31. Each motor 311 can be mounted in any suitable manneras by a. support 32 bridging between the plenum chamber side planels 22and 23. The propellers 30 rotate to move the air upwardly and outthrough the open top of the plenum chamber 21.

Accordingly, one stream of outside air is drawn downwardly through themain condenser chamber 25 through the open top thereof into the bottomof the shell and thence upwardly through the plenum chamber 21 to bedischarged through the open top thereof. A second stream of outside airis drawn downwardly through the intercondenser chamber 28 through theopen top thereof into the bottom of the shell and thence upwardlythrough the plenum chamber 21- to be discharged through the open topthereof. A third stream of outside air is drawn downwardly through theaftercondenser chamber 2@ through the open top thereof into the bottomof the shell and thence upwardly through the plenum chamber 21 to bedischarged through the open top thereof.

Main Condenser Openings 35 and 36 are provided in the portions of thefront and rear walls 16, 18 forming the main condenser chamber and tothe margin of the opening is secured a tube sheet 37 forming part of amain condenser 38 and to this tube sheet is secured both a steam orvapor inlet header 39 and a non-condensible or air outlet header 40, thelatter being arranged above the steam or vapor inlet header 39. Thesteam or vapor to be condensed is admitted to the steam or vapor header39 through an inlet 42 and thence passes through a series of maincondenser tubes 43 across the main condenser chamber 25, the oppositeends of which connect with the tube sheet 44 of a condensate header 45.This condensate header encloses the opening 36 and is divided into acondensate outlet chamber 46 and an air-vapor chamber 48 by an internalhorizontal partition 49 above the tubes 43 and extended partway acrossthe interior of the header and by a screen 50 extending downwardly fromthe outboard raised edge of this partition 49 to the lower part of theheader 45 and with the partition 49 isolates the chamber 46 from thechamber 48 so that steam or vapor and air entering the chamber 48 isrequired to pass through the screen 50. The horizontal partition 49 isprovided with weep holes w. This screen is preferably made of matted orintertwined metal strands so as to remove any entrained water from thepassing mixture of vapor and air. This removed water, together with thecondensate formed on passing through the main condenser tubes 43, flowsout through an outlet 51 which at the bottom of the header 45 canconnect with a hot well (not shown).

A bundle of air devaporizing or subcooling tubes 55 extend from the tubesheet 44 above the partition 49 to that portion of the sheet 37 enclosedby the air outlet header 40. This air outlet header 40 is divided into acondensate collecting chamber 58 and an air-vapor chamber 59 by a screen60 which insolates these chambers from each other so that the mixture ofair and vapor is required to pass through the screen, this screen alsobeing in the form of intertwined or matted metal strands so as to removeany entrained liquid from the mixture of air and vapor passingtherethrough.

An important feature of the invention resides in the inclusion of asmall number of reflux drain tubes 61 between the headers 40 and 45 andreturning any condensate from the bottom of the condensate collectingchamber 58 of the air outlet header 40 to the condensate outlet chamber46, these reflux or drain tubes 61 each having a vertical leg 62 ofsufficient length to maintain a column of liquid 63 therein, the heightof this column of liquid 63 being determined by the pressure drop acrossthe air devaporizing or subcooling tubes 55 and through the screen 50.This column 63 of liquid siphons the condensate from the condensatecollecting chamber 58, where a lower pressure prevails, to thecondensate outlet chamber 46 where the pressure is slightly higher.

Any condensate accumulating on top of the horizontal shelf or partition49 will pass through the weep holes w provided in that partition 49 andwill thus be guided into the condensate outlet chamber 46.

The air-vapor mixture outlet connection 65 from the air outlet header 40connects via a pipe 66 with a steam jet air ejector 68 which is suppliedwith steam from a steam line 69 and which forms a first stage jet airejector. The steam jet air ejector 68 discharges, at an intermediatevacuum, into an outlet line 70.

lntercondenser This line 70 discharges into the inlet 42a of anintercondenser 38a in the intercondenser chamber 28. Except for size theconstruction of this intercondenser 38a is identical with the maincondenser 38 and a detailed description is not repeated, correspondingparts being distinguished by the suffix a, and the tube sheets 37a and44a of the intercondenser being secured across openings 35a and 36aformed in those portions of the front and rear walls 16, 18 forming theintercondenser chamber 28. The steam air ejector 68:: from theintercondenser 38a, and which forms a second stage steam jet airejector, discharges into a line 71 leading to an aftercondenserindicated generally at 72.

A ftercondenser This aftercondenser 72 is arranged across theaftercondenser chamber 29 and comprises an inlet header 75 across anopening 67 in that portion of the front wall 16 forming the upper partof the aftercondenser chamber 29. The line 71 connects with this inletheader 75, and a series of serpentine tubes 76 filling theaftercondenser chamber 29 connect this inlet header 75 with an outletheader '78. These tubes 76 are preferably provided with an extendedsurface in the form of parallel spaced plates 77 secured thereto, theseplates serving to improve the heat transfer from the tubes to thepassing outside air. The outlet header 78 is arranged to close anopening 79 in that portion of the front wall 16 forming the lower partof the aftercondenser chamber 29 and is provided with an outlet nipple80 leading to the atmosphere with a downward drain 81 and an upward vent82.

Main Condenser Spray Water System The main condenser 38 is cooled by acaptive body of water 85 which is continuously revolved over theexternal surfaces of the condensing tubes 43 and air devaporizing orsubcooling tubes 55. The heat being so received by this body of water issteadily surrendered to the stream of air moving through the maincondenser chamber 25, the wet tubes and the falling water between themproviding the necessary contact surface for the transmission of heat andwater vapor from the captive body of water to the stream of coolant air.The mass transfer of water to air occurs by evaporation and the heatsurrendered by the body of water 85 to the air is thereforepredominantly latent.

The body of water 85 is contained in the sump 11, separated from anotherbody of water 86 contained in the sump by a partition 88. Each ofthesebodies of water can be supplied with make-up water in any suitablemanner (not shown), and the body of water 85 is withdrawn by a pump 89which discharges into a line 90 connected with a spray tree 91 in themain condenser chamber 25 above the air devaporizing or subcooling tubes55 of the main condenser 38. This spray tree includes a multiplicity ofnozzles 92 directing sprays of water 93 downwardly over all portions ofthe tubes 55, 61 and 43 of the main condenser 38, this water evaporatingto use the latent heat of the water in providing the cooling effect forthese tubes. The excess water from these tubes falls onto the inclineddrain panel 12 from which it returns to the body of water 85 in the sump11.

lntercona'enser Spray Water System The intercondenser 38a is cooled inexactly the same manner as the main condenser 38, its tubes being wettedby recirculated spray water supplied from the body of water 86 in thesump 11 by means of a pump 95. This pump discharges into a line 96connected with a spray tree 98 in the intercondenser chamber 28 abovethe air devaporizing or subcooling tubes 55a of the intercondenser 33a.The spray tree includes a multiplicity of nozzles 99 directing sprays ofwater 100 downwardly over all portions of the tubes 55a, 61a and 43a ofthe intercondenser 38a, a portion of this water evaporating to use thelatent heat of the water in providing the cooling effect for thesetubes.

The excess water from these tubes fall into a trough 191 the ends ofwhich can be closed by the front and rear walls 16, 18 of the casing andone longitudinal edge of which can be secured to the lower edge of thevertical partition 26 which for this purpose preferably extends belowthe intercondenser chamber 28 and the aftercondenser chamber 29 which itseparates. The spray water collecting in the trough 101 escapes throughan outlet or drain pipe 102 which returns the spray water to the body ofwater 86 contained with the sump 11.

Operation It is assumed that the fans 30 are operating to move the airin the plenum chamber 21 upwardly, this causing three streams ofatmospheric air to move downwardly past the tubes of the main condenser38, intercondenser 38a, and aft'ercondenser 72, respectively. Thus oneof the streams of outside air is drawn downwardly through the maincondenser chamber 25 through the open top thereof into the bottom of theshell 11] and thence upwardly through the plenum chamber 21 to bedischarged through the open top thereof. A second stream of outside airis drawn downwardly through intercondenser chamber 28 through the opentop thereof into the bottom of the shell and thence upwardly through theplenum chamber 21 to be discharged through the open top thereof. A thirdstream of outside air is drawn downwardly through the aftercondenserchamber 29 through the open top thereof into the bottom of the shell andthence upwardly through the plenum chamber 21 to be discharged throughthe open top thereof.

It will also be assumed that the spray water pump 89 is in operation towithdraw spray water from the body 85 and discharge it in the form ofdownwardly directed sprays 93 from the spray tree 91 against the tubesof the main condenser 38 to wet these tubes and evaporate thereon, theexcess spray water falling on its inclined drain panel 12 and beingreturned to the body of water 85.

It will also be assumed that the spray water pump 95 is in operation towithdraw water from the body 86 in the sump 11 and to discharge it inthe form ofdownwardly directed sprays 194 from the spray tree $8 overthe tubes of the intercondenser 38a to wet these tubes and evaporatethereon. The excess Water from these tubes falls into the trough 101 andis returned by the drain line 1112 to the body of water 86.

It will also be assumed that the steam or vapor to be condensed issupplied to the inlet 42 of the main condenser 38 and that thecondensate outlets 51 and 51a of the main condenser 33 and theintercondenser 38a, respectively, are connected to a hot well tomaintain a vacuum in the condensate headers 45 and 45a.

It will also be assumed, as an example of operation,

, that the outside air is at 90 dry bulb and 75 wet bulb temperature.

The vapor or steam to be condensed enters the inlet header 3% of themain condenser 38 at 42 and passes through the main condenser tubes 43in which condensation takes place, the condensate entering thecondensate outlet chamber 46 of the condensate header 45 and thecondensate flowing out at 51 into the hot well (not shown) whichmaintains a vacuum in the condensate header 45. Assuming that thecondensing pressure in the main condensing tubes 43 to be 2" Hg absoluteand the condensing temperature to be 101 F, the temperature of the spraywater in the body 85 in the sump 11 would be in the order of 89 F., thisrecirculating water wetting the tubes 43 and evaporating thereon toprovide the principal cooling effect in condensing the vapor passingtherethrough.

The vapor or steam, however, contains a very considerable quantity ofair as a non-condesible gas, this air being admitted in solution withthe boiler feed water and also entering through leakage into the systemmaintained under vacuum by the present vacuum producing condenser. Thisair mixes with the steam or vapor in any proportion if the steam is atthe saturation temperature corresponding to the prevailing pressure.

The steam air ejectors 63, 68a perform best when handling an air-vapormixture containing the least amount of vapor. This is because the airejectors handle a certain weight of gaseous fluid and hence the portionof vapor in the air-vapor mixture greatly reduces the air removalcapacity of the air ejectors.

Accordingly the air-vapor mixture from the condensate outlet chamber 46in the condensate header 45 is required to pass through the screen 511of matted metal strands so that any entrained liquid is removedtherefrom.

The resulting air-vapor mixture entering the air-vapor chamber 48 leavesthrough the air devaporizing or subcooling tubes 55 above the maincondensing tubes 43 and through which the air-vapor mixture from themain condensing tubes passes before reaching the first stage steamejector 68.

The important feature of locating the air devaporizing or subcoolingtubes 55 above the main condenser 33, causing upwardly moving air toseparate and escape from the downward gravity flow of condensate in thecondensate outlet chamber 46, this separation being facilitated by themovements in opposite directions, is retained from my previous inventiondescribed in my Patent 2,570,247. A feature of the present invention isthe cooling of the air devaporizing or subcooling tubes 55 by a streamof air taken directly from the outdoors at lowest available wet bulbtemperature (lowest enthalpy). The cooling effect to which these airdevaporizing or subcooling tubes 55 are thus subjected is greater thanif these tubes were downstream from the main condenser tube 43 withreference to the air stream.

The cooling elfect to any portion of the sprayed, wet heat transfersurface is in direct proportion to the difference between the enthalpyof an air film saturated with water vapor at the spray contacttemperature and the enthalpy of the bulk air stream. As the airdevaporizing or subcooling tubes 55 are served directly by the outdoorair entering the open top of the main condenser chamber 25 by virtue ofthe downward flow of this stream of air, both air enthalpies discussedin the preceding sentence will be lower and their difference greater.Accordingly, more heat will be transferred and a lower temperature ofthe air-vapor mixture will be achieved, resulting in maximumdevaporization.

A portion of the liquid condensing in these air devaporizing orsubcooling tubes 55 may flow back through these same tubes in the formof open streams onto a shelf or partition 49 in the condensate header 45and thence through weep holes w provided in that shelf or partition 49,in order to reach the condensate outlet chamber 46 and join the,condensate discharged into this chamber by the main condenser tubes 43.The remaining portion of the liquid condensing in these air devaporizingor subcooling tubes 55 will be entrained by the air-vapor mixture intothe condensate collecting chamber 58. The air-vapor mixture (withreduced vapor) continues through the matted strand screen 66 in the airoutlet header 40 which removes any entrained liquid therefrom.

This entrained liquid, plus any liquid condensing in the air outletheader 40, flows to the bottom of this header and through the refluxdrain pipes 61 back into the condensate header 45 to join the liquidpreviously condensed in flowing out through the outlet 51 to the hotwell (not shown). A lower pressure obtains in the condensate collectingchamber 5d of the air outlet header 4%) than in the condensate header45, due to the pressure drop along the air devaporizing or subcoolingtubes 55. To permit the reverse flow of condensate in the reflux draintubes 61 against this pressure drop, and at the same time otherwiseisolate these headers from each other, each reflux drain tube isprovided somewhere along its length with a vertical leg 62 in which acolumn of liquid 63 forms, the height of this column being determined bythe pressure drop. This column of liquid 63 isolates the headers 4-0 and4-5 from each other and permits the flow of condensate from the lower tothe higher pressure header.

With the assumed dry and wet bulb ambient air conditions and the assumedcondensing temperature of 101 F. and condensing pressure of 2" Hgabsolute, the air, saturated with vapor, would enter the first stageejector 68 at a pressure of approximately 1.9" Hg absolute and at 92 F.The mixture of this air with the steam driving the ejector 68 results inincreased outlet pressure and temperature at the discharge from theejector, say, in the order of 6" Hg absolute and 190 F.

This air-vapor mixture from the outlet line 70 of the first stageejector 68 enters the inlet header 39a of the condenser 38a and passesthrough the tubes 43a in which condensation takes place, the condensateentering the condensate outlet chamber 46a of the condensate header 45aand the condensate flowing out at 51a into the hot well (not shown)which maintains a vacuum in the condensate header 450. Under the assumedoperating conditions the condensing pressure in these condensing tubes43:: would be in the order of 6" Hg absolute and the condensingtemperature would be in the order of 141 F. and with the assumed ambientair conditions of 75 F. wet bulb and 90 F. dry bulb, the temperature ofthe recirculating spray water from the body 86 would be in the order of107 F., this recirculating water wetting the tubes 43a and evaporatingthereon to provide the principal cooling effect in condensing the vaporpassing therethrough. The air-vapor mixture from the condenser outletchamber 46a in the condenser header 45a passes through the screen 50:!of matted metal strands to remove any entrained liquid therefrom and theresulting air-vapor mixture entering the air-vapor chamber 43a leavesthrough the air devaporizing or subcooling tubes 55a above thecondensing tubes 43a and through which the air-vapor mixture from thecondensing tubes passes before reaching the second stage steam ejector63a.

As with the main condenser 38, a feature of the intercondenser 38a isthat these air devaporizing or subcooling tubes 55a are served directlyby the fresh air entering the shell by virtue of the downward flow ofthis stream of air. The cooling effect of this fresh entering air is atits maximum with the result that the subcooling of these devaporizing orsubcooling tubes 55a is greater than if these tubes were downstream fromthe main condenser tubes 43 with reference to the air stream.Accordingly maximum devaporization of the air is obtained in these tubeswith the direct use of fresh air over the wet external tube surfaces.

A portion of the liquid condensing in these devaporizing or subcoolingtubes 5541 may flow back through these same tubes in the form of openstreams onto a shelf or partition 94a in the condensate header 45a andthence through weep holes w provided in that shelf or partition 45a, inorder to reach the condensate outlet chamber 46a and join the condensatedischarged into this chamber by the intercondensing tubes 43a. Theremaining portion of the liquid condensing in these devaporizing orsubcooling tubes 55a will be entrained by the air-vapor mixture into thecondensate collecting chamber 58a.

The air-vapor mixture continues through the matted strand screen 60a inthe air outlet header a which removes any entrained liquid therefrom.This entrained liquid, plus any liquid condensing in the air outletheader 40a, flows to the bottom of this header and through the refluxdrain pipes 61a back into the condensate header a. to join the liquidpreviously condensed in flowing out through the outlet 51a to the hotwell (not shown). A lower pressure obtatins in the air outlet header 40athan in the condenser header 45a, due to the pressure drop along the airdevaporizing or subcooling tubes a. To permit the reverse flow ofcondensate in the reflux drain tubes 61:: against this pressure drop,each reflux drain tube is provided somewhere along its length with a avertical leg 62a in which a column of liquid 63a forms, the height ofthis column being determined by this pressure drop. This column ofliquid 63a isolates the headers 40a and 45a. from each other and permitsthe flow of condensate from the lower to the higher pressure header.

With the assumed operating conditions, the air, saturated with watervapor, would enter the second stage ejector 63a at a pressure ofapproximately 5.5 Hg absolute at 120 F. The mixture of this air with thesteam driving the second stage ejector 6811 results in increased outletpressure and temperature in the ejector, say, in the order of 31" Hgabsolute and 230 F.

This mixture of air and steam is continued via the line 71 to the inletheader 75 of the aftercondenser 72 and passes through the finnedserpentine tubes 76 thereof to its outlet header 78 and drain 80 whichleads to atmosphere with the downward drain 81 and upward vent 82. Thisaftercondenser is served by the atmospheric air at the assumed 90 F. drybulb, the condensate leaving the drain 80 at 212 F. and thenon-condensible gas being discharged into the atmosphere.

Features of the Condenser From the foregoing it will be noted that thepresent vacuum producing condenser is characterized, as compared withpatented condenser, by the following features:

Separate streams of fresh air serve the main condenser 33,intercondenser 38a and aftercondenser 72 thereby to provide the maximumcooling effect for each.

With both the main condenser 38 and intercondenser 38a, the fresh airfirst passes the air devaporizing tubes 55 and 55a thereby to reduce thetemperature of these tubes to the minimum with maximum devaporization ofthe air passing therethrough. The stream is thereafter used to cool theprincipal condensing tubes 43, 43a.

Since the normal separation of uncondensible gas is upwardly from thecondensate with the gas devaporization tubes above the principalcondensing tubes, this serving of the gas devaporization with fresh airis achieved by downward movement of the air first past the gasdevaporization tubes and then past the principal condensing tubes.

With downward flow of air and downward discharge of the spray water, themovement is concurrent with each other.

The barrier screens of matted metal strands across the headers 45, 40,45a and 40a served to separate the airvapor mixtures from thecondensate, particularly as to any entrained condensate and forms a verysimple means for effecting such separation.

The vertical legs 62 of the reflux or condensate drain tubes 61 produceliquid seals 63 which permit movement of the condensate from a lowerpressure to a higher pressure header but otherwise isolates theseheaders from each other.

The segregation of the lower temperature water 85 serving the maincondenser 38 from the higher temperature water 86 serving theintercondenser 38a avoids needless raising the temperature of the water85 serving the main condenser, with resulting increased capacity of bothits gas devaporization tubes 55 and its main condensing tubes 43.

I claim:

1. A vacuum producing condenser for vapors containing non-condensiblegases, comprising a shell having a main condenser chamber communicatingwith the atmosphere at its top and with the interior of the shell at itsbottom and also having an intercondenser chamber communicating with theatmosphere at its top and with said interior of said shell at its bottomand also having a sump at its bottom for spray water falling from saidchambers, means discharging air from said interior of said shell tocreate a downward flow of outside air through each of said chambers,main condenser tubes across said main condenser chamber having an inletfor the steam to be condensed and having an outlet, a first spray treeabove said main condenser tubes to discharge water downwardly thereon, asteam jet ejector, means connecting said outlet of said main condensertubes with the suction inlet of said steam jet ejector, intercondensertubes across said intercondenser chamber and having an outlet and havingan inlet connected to the discharge of said steam ejector, a secondspray tree above said intercondenser tubes to discharge water downwardlythereon, and means recirculating water from said sump to said spraytrees.

2. A vacuum producing condenser as set forth in claim 1 wherein saidshell has an aftercooler chamber open to the atmosphere on one side andto said interior of said shell at its other side, and additionallyincluding a second steam jet ejector, means connecting the suction inletof said second steam jet ejector with said outlet of said intercondensertubes, an aftercondenser in said afterconser chamber and having an inletand an atmospheric outlet and means connecting the discharge of saidsecond steam jet ejector with said inlet of said aftercondenser.

3. A vacuum producing condenser as set forth in claim 1 wherein saidmeans for discharging air from the interior of said shell comprisesmeans providing a plenum chamber open to the atmosphere at its top andto said interior of said shell at its bottom and arranged between saidmain condenser and intercondenser chambers, and fan means in said plenumchamber propelling the air therein upwardly.

4. A vacuum producing condenser as set forth in claim 1 wherein saidsump has a partition dividing it into two sections with means leadingthe spent spray water from said main condensing chamber to one of saidsections and means leading the spent spray water from saidintercondenser chamber to the other of said sections and wherein saidwater recirculating means includes a first pump moving water from saidone of said sump sections to said first spray tree and a second pumpmoving water from said other of said sump sections to said second spraytree.

5. A vacuum producing condenser as set forth in claim 1 wherein saidmeans connecting the outlet of said main condenser tubes with said steamjet ejector includes a bundle of gas devaporizing tubes arranged in saidmain condenser chamber above said main condenser tubes and wherein saidfirst spray tree discharges water downwardly on said gas devaporizingtubes.

6. A vacuum producing condenser as set forth in claim 5 additionallyincluding a second steam jet condenser and means connecting the suctioninlet thereof with said outlet of said intercondenser.

7. A vacuum producing condenser as set forth in claim 6, said meansconnecting the suction inlet of said second steam jet injector with saidoutlet of said inter- 10 condenser includes a bundle of gas devaporizingtubes arranged in said intercondenser chamber above said intercondensertubes and wherein said second spray tree discharges water downwardly onsaid last mentioned bundle of gas devaporizing tubes.

8. In a vacuum producing condenser for vapors containing non-condensiblegases, a shell having a condenser chamber communicating with theatmosphere at its top and with the interior of said shell at its bottom,a sump at the bottom of said shell collecting spray water falling fromsaid condenser chamber, means discharging air from said interior of saidshell to create a downward flow through said condenser chamber, a bundleof condenser tubes across said condenser chamber, an inlet header at theinlet end of said bundle of condenser tubes, a condensate header at theoutlet end of said bundle of condenser tubes and having a portionprojecting above said bundle of condenser tubes, a return header abovesaid inlet header, a bundle of gas devaporization tubes across saidcondenser chamber and connecting the return header with said portion ofsaid condensate header projecting above said bundle of condenser tubes,a steam jet ejector having its suction inlet connected to said returnheader, a spray tree above said bundle of gas devaporization tubes todischarge water downwardly on said bundles of gas devaporization andcondenser tubes, and means recirculating water from said sump to saidspray trees.

9. The combination set forth in claim 8 additionally including a screenacross the interior of said condensate header through which the mixtureof vapor and gas is required to pass before entering said bundle of gasdevaporization tubes.

10. The combination set forth in claim 9 wherein said screen is in theform of intertwined strands.

11. The combination set forth in claim 10 additionally including asecond screen of intertwined strands across the interior of said returnheader and through which the mixture of vapor and gas is required topass before entering said steam jet ejector.

12. The combination set forth in claim 8 including a reflux drain tubeconnecting the bottom of said return header with the interior of saidcondensate header and wherein said reflux drain tube includes a verticalleg adapted to support a column of liquid the height of which isdetermined by the differential in pressure between said headers.

Graham Feb. 6, 1934 Deverall Dec. 8, 1953

1. A VACUUM PRODUCING CONDENSER FOR VAPORS CONTAINING NON-CONDENSIBLEGASES, COMPRISING A SHELL HAVING A MAIN CONDENSER CHAMBER COMMUNICATINGWITH THE ATMOSPHERE AT ITS TOP AND WITH THE INTERIOR OF THE SHELL AT ITSBOTTOM AND ALSO HAVING AN INTERCONDENSER CHAMBER COMMUNICATING WITH THEATMOSPHERE AT ITS TOP AND WITH SAID INTERIOR OF SAID SHELL AT ITS BOTTOMAND ALSO HAVING A SUMP AT ITS BOTTOM FOR SPRAY WATER FALLING FROM SAIDCHAMBERS, MEANS DISCHARGING AIR FROM SAID INTERIOR OF SAID SHELL TOCREATE A DOWNWARD FLOW OF OUTSIDE AIR THROUGH EACH OF SAID CHAMBERS,MAIN CONDENSER TUBES ACROSS SAID MAIN CONDENSER CHAMBER HAVING AN INLETFOR THE STEAM TO BE CONDENSED AND HAVING AN OUTLET, A FIRST SPRAY TREEABOVE SAID MAIN CONDENSER TUBES TO DISCHARGE WATER DOWNWARDLY THEREON, ASTEAM JET EJECTOR, MEANS CONNECTING SAID OUTLET OF SAID MAIN CONDENSERTUBES WITH THE SUCTION INLET OF SAID STEAM JET EJECTOR, INTERCONDENSERTUBES ACROSS SAID INTERCONDENSER CHAMBER AND HAVING AN OUTLET AND HAVINGAN INLET CONNECTED TO THE DISCHARGE OF SAID STEAM EJECTOR, A SECONDSPRAY TREE ABOVE SAID INTERCONDENSER TUBES TO DISCHARGE WATER DOWNWARDLYTHEREON, AND MEANS RECIRCULATING WATER FROM SAID SUMP TO SAID SPRAYTREES.